1. Field of the Invention
This invention pertains generally to water treatment systems, and more particularly to water treatment systems having electrolytic cells.
2. Description of Related Art
Chlorine is the most common disinfectant used in water and wastewater treatment systems in the world. Among a number of other applications, chlorine is commonly used in applications ranging from potable water, odor and corrosion control, and wastewater treatment to irrigation systems and food and beverage processing.
Historically, gaseous chlorine was the most prevalent form of chlorination system in the United States; however, the use of liquid sodium hypochlorite is increasing in water and wastewater treatment applications due to safety concerns associated with the use, storage and transportation of chlorine gas.
Transporting bulk chlorine on crowded highways and into residential areas has become a major safety concern. Federal and local authorities have recognized this problem and are dictating better solutions to this problem. For example, implementation of the Clean Air Act (CAA) Risk Management Plan (RMP) by the USEPA for the storage of hazardous chemicals (June 1999) and the re-registration of chlorine gas by the USEPA Office of Pesticide Programs as a pesticide (Fall 2001) have further accelerated the use of liquid sodium hypochlorite in the water and wastewater treatment industry.
More stringent regulation of toxic gases and accidental releases of chlorine have required industry professionals to seek alternative methods of disinfection. Pressurized chlorine gas has become regulated to the point where many utilities have evaluated the alternatives and found on-site generation of sodium hypochlorite to be their best available technology for disinfection.
On-site chlorine generation systems have been developed to solve this problem. However, existing systems are inefficient, requiring large amounts of energy to produce the amounts of chlorine required. In addition, existing chlorine generation systems require constant monitoring and frequent maintenance from material buildup in the system.
In addition, most conventional electrochemical processes having D.C. electrodes rely on automatic current control where amperage is fixed and voltage is allowed to float. These systems typically utilize phase angle-fired SCR control of the rectification process, which account for the vast majority, if not all, of the failures related to the D.C. rectification process.
The water storage systems currently used to hold treated water also have drawbacks. These large water reservoirs are prone to water quality problems as they are typically stagnant with as little as one to two percent turnover per day. This lack of turnover allows for biological re-growth, nitrification, and temperature stratification. These factors can all compound to produce a poor or even unhealthy water quality leading to consumer complaints and related water quality issues within the distribution system.
Therefore, an object of the present invention is to provide an improved chlorine generation system that efficiently and reliably generates chlorine from a base solution.
Another object of the present invention is a chlorine generation system that is self-cleaning and therefore requires minimal maintenance to operate.
Yet another object of the present invention is an oxygen generation system that generates oxygen via electrolytic liberation of hydrogen in water.
Yet another object of the present invention is to provide an improved water treatment delivery system.
At least some of the above-mentioned objectives will be met in the invention described hereafter.